IV. BÜTTIKOFER'S GUENON. CERCOPITHECUS BUETTIKOFERI.
Cercopithecus buettikoferi, Jentink, Notes, Leyd. Mus., viii., p. 56 (1886); Sclater, P. Z. S., 1893, p. 244.
Characters.—Büttikofer's Guenon agrees in all respects with C. petaurista, but wants the black band from ear to ear round the vertex. Of this band "there is no trace, in a series of eight specimens, containing adults and young, males and females" (Jentink). Irides brown.
Distribution.—West Africa: Liberia.
V. MARTIN'S GUENON. CERCOPITHECUS MARTINI.
Cercopithecus martini, Waterh., P. Z. S., 1838, p. 58; 1841, p. 71; Martin, Mammif. Anim., p. 542 (1841); Gray, Cat. Monkeys Brit. Mus., p. 21 (1870); Scl., P. Z. S., 1884, p. 176, pl. xiv.; 1893, p. 245.
Cercopithecus nictitans, Schl., Mus. Pays-Bas, vii., p. 89 (1876).
Description.—Allied to C. petaurista. Fur tolerably long and but loosely applied to the body. Face naked; whiskers bushy; beard short; tail very long; callosities small. Length of body (type specimen), 22 inches; tail, 26. Length of a female, 19 inches; tail, 24. General colour of head, back, and upper side of the basal part of the tail olive-green, distinctly annulated, the hairs being grey at their base, ringed above with several bars of yellowish-green and black. Face blue; nose-spot, commencing in the middle of the ridge, and extending over its sides and the upper and lower lips, yellowish-white; a black line extending up the ridge of the nose from the end of the white spot to the brow and encircling the eyes; a black bar crossing the forehead from ear to ear; whiskers green; beard white; throat, chest, under side of body, inside of limbs and under side of three-fourths of the tail, greyish-white; fore-arms black; legs black; the arms and thighs of the same colour as the back; upper side of the tail beyond the basal region, and its terminal portion, black; hands and feet black.
As Dr. Sclater has pointed out (loc. cit.): "It is at once distinguishable from C. petaurista by the black fore-limbs and feet, by the greenish colour on the tail above; the greenish cheeks, without any white stripe beneath the ears, and the bluish skin of the face."
Distribution.—Martin's Guenon is generally brought to Europe from the island of Fernando Po, where it is probably indigenous. It may also inhabit the neighbouring coast of Western Africa.